Try just the "<"... that's the last thing on the prompt line. If that doesn't solve the issue then you will need to analyze the dump_log files and see where it's timing out. 
use Net::Telnet;
 
my $telnet3;
$telnet3 = new Net::Telnet(timeout => 10,
                Errmode => 'die'
                Prompt => '/</');
 
$telnet3->open('10.200.16.58'); 
$telnet3->login('IATEST', 'TESTBED');
@lines = $telnet3->cmd("who");

[download]
regexes

In reply to Re^6: Net::Telnet timed out when logging in by regexes
in thread Net::Telnet timed out when logging in by poolboi

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